Then experiment to get the best settings. Watch the graph lines for the best STABLE ping.

On DSL I'm using: (now on cable)

cl_cmdrate "100"
cl_updaterate "45"

rate "20000"
I picked up this rate setting from hltoolz. Many ppl use rate "9999".

To be honest, I have forgotten what the net_graph "1" lines specifically represent. IN A PERFECT WORLD, the lines would be solid and flat without any spikes or breaks. You want to tweak your settings using net graph one. It does help.

For a starting point, enter a game and use:

cl_cmdrate "100"
cl_updaterate "100"

Then change that to cl_updaterate "20". Twenty is probably not a realistic setting but it will let you see the difference it makes in its graph line and in your PING. Start raising the setting by increments of 5-10 points until the line is as flat/stable as it gets. THEN STOP. A lower cl_updaterate will lower your ping but you don't want to sacrifice quality for speed or vice versa.

Next do the same thing with cl_cmdrate.

Just take your time with it, it's easy to see.

-edit - groovyf, thanks for mention of the net_graphpos 2 command. After having the net_graph centered for years, I totally did not think about it popping up to the side for a new user.

-edit2 from SME -
"Changing rate will affect your Steam setting for your selected internet speed.
For 2M cable 15-20K might be fine but for 10M cable it needs to be 25-30K."